// Symbol在对象中的作用它的意思是全局标记

var a = new String;
var b = new Number;
var c = new Boolean;
var d = new Array;
var e = new Object; 
var f= Symbol();
console.log(typeof(d));

var g = Symbol('jspang');
console.log(g);
console.log(g.toString());

var jspang = Symbol();
var obj={
    [jspang]:'技术胖'
}
console.log(obj[jspang]);
obj[jspang]='web';
console.log(obj[jspang]);

var obj={name:'jspang',skill:'web',age:18};
 
for (let item in obj){
    console.log(obj[item]);
}


// let obj={name:'jspang',skill:'web'};
// let age=Symbol();
// obj[age]=18;
// for (let item in obj){
//     console.log(obj[item]);
// } 
// console.log(obj);